Missing preempt count set on scheduler IPI.

-ck

---
 include/linux/sched.h |    5 -----
 kernel/sched/bfs.c    |   12 ++++++++++++
 2 files changed, 12 insertions(+), 5 deletions(-)

Index: linux-3.16-ck2/include/linux/sched.h
===================================================================
--- linux-3.16-ck2.orig/include/linux/sched.h	2014-08-25 09:45:58.094543864 +1000
+++ linux-3.16-ck2/include/linux/sched.h	2014-08-25 09:45:58.092543864 +1000
@@ -2510,12 +2510,7 @@ static inline void set_task_comm(struct
 extern char *get_task_comm(char *to, struct task_struct *tsk);
 
 #ifdef CONFIG_SMP
-#ifdef CONFIG_SCHED_BFS
-/* scheduler_ipi does nothing on BFS */
-static inline void scheduler_ipi(void) { }
-#else
 void scheduler_ipi(void);
-#endif
 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
 #else
 static inline void scheduler_ipi(void) { }
Index: linux-3.16-ck2/kernel/sched/bfs.c
===================================================================
--- linux-3.16-ck2.orig/kernel/sched/bfs.c	2014-08-25 09:45:58.094543864 +1000
+++ linux-3.16-ck2/kernel/sched/bfs.c	2014-08-25 09:45:58.092543864 +1000
@@ -1505,6 +1505,18 @@ ttwu_stat(struct task_struct *p, int cpu
 #endif /* CONFIG_SCHEDSTATS */
 }
 
+#ifdef CONFIG_SMP
+void scheduler_ipi(void)
+{
+	/*
+	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
+	 * TIF_NEED_RESCHED remotely (for the first time) will also send
+	 * this IPI.
+	 */
+	preempt_fold_need_resched();
+}
+#endif
+
 static inline void ttwu_activate(struct task_struct *p, struct rq *rq,
 				 bool is_sync)
 {